5 years ago, the average age of 4 boys was 9 years. Due to one boy added now to the group, the present age of the five boys becomes 15 years. Accordingly, what is the present age of the new boy?

A motor car goes from Mumbai to Pune at a speed of 20 km per hours and returns from there at a speed of 30 km per hour.…

The average temperature of Monday, Tuesday and Wednesday was 30 degree C and the same for Tuesday, Wednesday and Thursd…

A mixture of milk and water weighing 55 kg has a proportion of 7: 4. To make the proportion as 7: 6, how much water wil…

A completes a work in 4 days and B does it in 6 days. If they both work together, in how many days they will finish the…

A father is elder by 7 years than mother and the mother is three times the age of her daughter. The daughter at this ti…

Six bells start ringing at the same time. Then they ring after an interval of 2,4,6,8,10 and 12 seconds each. In 30 min…

Tap A fills a tank in 8 hours. Tap B fills it in 6 hours. If both the taps A and B are started and after 2 hours tap A…

The holding of two halfcircular pots is 6.4 liters and 21.6 liters. Accordingly, what is the proportion of their intern…

Rs. 5000 becomes Rs. 5700 in one year. Accordingly, what amount Rs. 7000 will become at the same simple rate of interes…

The population of a city is 15000. If the number of males in the city increases by 8 % and that of females increases by…